CN1713234B

CN1713234B - Low frequency transcutaneous telemetry to implanted medical device

Info

Publication number: CN1713234B
Application number: CN2005100796695A
Authority: CN
Inventors: 小威廉·L·哈斯勒; 小丹尼尔·F·德卢戈斯
Original assignee: Ethicon Endo Surgery Inc
Current assignee: Ethicon Endo Surgery Inc
Priority date: 2004-06-24
Filing date: 2005-06-24
Publication date: 2010-05-05
Anticipated expiration: 2025-06-24
Also published as: BRPI0502400A; CN1713234A; KR20060048509A; RU2005118393A; US20050288740A1; BRPI0502400A8; JP2006006949A; MXPA05006880A; AU2005202384A1; EP1637180A1; CA2510078A1; AU2005202384B2

Abstract

An implantable medical device advantageously utilizes low frequency (e.g., 100 kHz or below) for telemetry communication with an external control module avoiding power dissipation through eddy currents in a metallic case of an implant and/or in human tissue, thereby enabling smaller implants using a metallic case such as titanium and/or allow telemetry signals of greater strength for implantation to a greater depth.

Description

Low frequency transcutaneous telemetry to the medical treatment device implanted

Technical field

The present invention relates to telemetry system, relate in particular to can be used in combination with low frequency transcutaneous NE BY ENERGY TRANSFER (TET) system with externally between control module and the medical implant apparatus transmission data the low frequency telemetry system.

Background technology

It is known that medical treatment device operation is implanted in patient's body to obtain the multiple beneficial effect.In order correctly to work in patient's body, reliable and constant the communicating to connect between medical implant apparatus and the external control module usually is necessary, thereby monitors performance or some patient parameter of implanted device and/or require implanted device to carry out some operation.This communicates to connect is realizing to the telemetry system more than the 30MHz at 100kHz with frequency of operation traditionally.These higher frequencies are used to make required coil dimension to minimize, and therefore coil are installed in the implanted device housing.It also is known that telemetry coil is placed into the implanted device outside so that use bigger coil.Therefore because electrical lead must extend to coil in the implanted device outside, do complicacy and the expense that has increased implanted device so then, and to the sealing that keeps housing with avoid the infringement of external coil has been proposed challenge.

Although the high frequency telesignalisation has reduced required coil dimension, this signal has also reduced the effective communication distance between the transceiver in the system.The transceiver of implanting usually must be placed to the tight below of patient skin surface so that communicate by letter with external transceiver effectively.Under short wavelength (that is, higher frequency), when signal when organizing dissipates on short distance.

The above high frequency telesignalisation of 100kHz more may cause producing electromagnetic interference (EMI) or with the consistency problem of other communication facilities, therefore additional restriction has appearred in federal regulations.Observing these regulations has increased time and the complexity of developing this implanted device, and will limit through-put power.

An example of the implantable device of being benefited from the use of telemetry system is an artificial sphincter, especially can adjust the bundle stomach band, this bundle stomach band comprises a hollow elasticity air bag, and it has around the plurality of fixed end points of the stomach position of patient's tight below, esophageal-gastric junction.These air bags can expand in the air bag and shrink by brine solution is incorporated into.Adjust in the bundle stomach band generally well-known, this brine solution must be expelled to subcutaneous ports with entry needle and arrive this port that is positioned under the skin surface.Described port is by conduit and described bundle stomach band hydraulic communication.Although effectively, it is desirable to avoid to use entry needle regulated fluid volume, reason is that this may cause the danger of infecting, and can make troubles with uncomfortable to the patient.

Different with aforementioned medical implant apparatus, the injector apparatus that is used for artificial sphincter is implanted to the thicker skin corium and the adipose tissue below of skin usually.It is especially true concerning the patient of the treatment of morbid oberity that this can adjust the conduct of bundle stomach band for common acceptance.And deeper implantation can make prescription on individual diagnosis person more comfortable.Yet thickness of tissue causes difficulty for efficient communication.

Therefore, for the bigger efficient communication scope between the primary and secondary transceiver is provided, and observe the FCC regulation as far as possible, be starved of the remote measurement that strengthens under than normally used more low frequency the medical treatment device that has dark implantation.

Summary of the invention

The present invention has overcome the above-mentioned of prior art and other shortcoming by a kind of telemetry system that is used for implantable medical device of working is provided under the frequency less than 100kHz, advantageously make eddy current losses minimize and allow to use metal shell to obtain littler implantation size. when the telemetry system transmission is more high-power, low frequency has been avoided the heating tissue. and, the low frequency telemetry system comprises the telemetry coil in the implantable device that is included in sealing, thereby guarantees the integrality of this device.

In a scheme of the present invention, telemetric circuit is crossed the physical boundary communication between the primary and secondary tank circuits with the combination of inductance and electric capacity, and described inductance and electric capacity combination are selected to the scope internal resonance that is used at 25-100kHz.Therefore, implantable medical device can the secondary telemetry coil in being included in its integral body be implanted deeply and still can be obtained reliable remote measurement.

Should obviously find out these and other target of the present invention and advantage from accompanying drawing and description thereof.

Description of drawings

Be attached in the instructions and as an illustration the accompanying drawing of a book part show embodiments of the invention, general description of itself and the invention described above and the specific descriptions one of following embodiment are used from explains principle of the present invention.

Fig. 1 is the structural drawing of display remoting system, and this telechirics comprises the low frequency power and the telemetry system of implantable medical device of the present invention system;

Fig. 2 is the synoptic diagram that shows low frequency TET power system of the present invention and telemetry system;

Fig. 3 is the synoptic diagram that shows a canonical form that is applicable to wave filter of the present invention;

Fig. 4 A is the diagram in the magnetic field of the primary and secondary power of telechirics of displayed map 1 and telemetry coil;

Fig. 4 B is the diagram in magnetic field of the primary and secondary coil of the power of displayed map 1 another embodiment and telemetry system, and prime power and telemetry coil are placed on around the ferrite core in this embodiment.

Embodiment

Now in detail with reference to the accompanying drawings, identical numeral components identical in all figure, in Fig. 1, remote control implantable medical device system 10 comprises telechirics 12, and this telechirics is advantageously carried out through skin NE BY ENERGY TRANSFER (TET) with by telemetry system 16 by TET power system 14 and carried out remote measurement.The

interior section

18,20 of TET power system 14 and telemetry system 16 lays respectively in the implantable medical device (" implanted device ") 22, and the two

exterior section

24,26 lays respectively in the external control module 28.Implanted device 22 and external control module 28 by physical boundary 30 at interval, this physical boundary shown in form in form by the dermal tissue that generally comprises the adipose tissue thick-layer.

Can be disclosed in the applying date from follow-on TET power supply and the benefited implantable two-way injection device of remote measurement is the common unsettled and patented claim owned together of four of on May 28th, 2004, the full content of described application is incorporated into this with for referencial use, its name is called (1) and " is used for the driving type piezoelectric actuator gasbag-type injector that hydrostatic control can be adjusted the bundle stomach band ", the invention people is William L.Hassler, Jr., sequence number is 10/857,762; (2) " be used for adjusting the metal bellows formula position feedback of the hydrostatic control of restrainting stomach band ", the invention people is William L.Hassler, Jr., and Daniel F.Dlugos, Jr., Rocco Crivelli, sequence number are 10/856,971; (3) " as the reversible injector pump of thermodynamic-driven formula of distance type bundle stomach band use ", the invention people is William L.Hassler, Jr., Daniel F.Dlugos, Jr, sequence number are 10/857,315; (4) " be used for the two-way injector pump that has volume braking that hydrostatic control can be adjusted the bundle stomach band ", the invention people is William L.Hassler, Jr., and Daniel F.Dlugos, Jr., sequence number are 10/857,763.

The exterior section 26 of telemetry system 16 comprises and is used to launch inquiry command and is electrically connected to an elementary controller 34 to import and to receive the order data signal from user or automatic programming device from primary. transceiver 32. primary. transceiver 32 that implanted device 22 receives response data. especially, elementary controller 34 is communicated by letter with elementary remote measurement arbiter 36, this arbiter is responsible for alleviating and cushioning through the up telemetry communication of elementary remote measurement output interface logical circuit 38 arrival primary. transceiver 32 and from the descending telemetry communication of primary. transceiver 32 through elementary telemetry interface differential amplifier input logic circuit 40. and to produce descending alternating magnetic field 42, this alternating magnetic field is transferred to implanted device 22. with order data to primary. transceiver 32 at selected radio frequency (RF) communication frequency low-resonance

The interior section 18 of telemetry system 16 also comprises the secondary transceiver 44 that concerns at interval with primary. transceiver 32, and is positioned at the opposition side on border 30 of the housing (not shown) of implanted device 22.In the present invention, secondary transceiver 38 is electrically connected to secondary controller 46.Especially, secondary controller 46 is communicated by letter with secondary remote measurement arbiter 48, and this arbiter is responsible for alleviating and is cushioned through secondary remote measurement output interface logical circuit 50 and arrives the up telemetry communication of secondary transceiver 44 and the descending telemetry communication that sends through secondary telemetry interface differential amplifier input logic circuit 52 from secondary transceiver 44.Secondary transceiver 44 by being used for downlink communication alternating magnetic field 36 and be used for alternating magnetic field 54 magnetic couplings of uplink communication to primary. transceiver 32.Magnetic flux from primary. transceiver 32 produces electric command signal in secondary transceiver 44.This command signal be applied in the implanted device 22 secondary controller 46 with the indication implanted device 22 work.Similarly, secondary transceiver 44 is electrically connected to controller 46 command response signals is transferred to the exterior section 26 of telemetry system 16 from implanted device 22.When requiring data transmission, transceiver 44 at selected RF frequency low-resonance to produce up alternating magnetic field 54.Be coupled in the primary. transceiver 32 in up magnetic field 54, and this primary. transceiver 32 produces the electric signal that is input to elementary controller 34.

Still with reference to figure 1, the exterior section 24 of TET power system 14 also comprises elementary feed circuit 56, and these elementary feed circuit are electrically coupled to power supply 58 with at selected power signal RF frequency low-resonance by power amplifier 60.Primary circuit 56 electric signal that is provided by power supply 58 is provided and produces alternating magnetic field 62.The interior section 18 of TET power system 14 comprises and the secondary power circuit 64 of elementary feed circuit 56 compositions every relation.Secondary power circuit 64 is arranged on the side on the border 30 opposite with the elementary feed circuit 56 of implanted device 22.Secondary power circuit 64 is electrically coupled to elementary feed circuit 56 by alternating magnetic field 62.Secondary power circuit 64 produces electrical power signal 66 from magnetic field 62.Power signal 66 by power conditioning circuitry 68 rectifications and adjusting and and be applied to implanted device driver 70, thereby be the various active parts power supplies of implanted device 22.

In Fig. 2, the TET power system 14 that belongs to telechirics 12 and the resonant circuit part of telemetry system 16 have been shown.Especially, primary. transceiver 32 comprises tuning tank circuit 72 in parallel, and this tank circuit has the electric capacity of being made up of one or more and telefault 76 capacitors 75 in parallel.Capacitor 75 and coil 76 are tuned to and produce resonance when controller 34 applies voltage under characteristic frequency.Similarly, secondary transceiver 44 comprises tuning tank circuit 78 in parallel, and this tank circuit has electric capacity 80 and telefault 62, and it is tuned under the frequency identical with elementary remote measurement tank circuit 72 and resonates.Equally as shown in Figure 2, elementary feed circuit 56 comprise tuning tank circuit in parallel, and this tank circuit has electric capacity 86 and the coil 88 that is tuned to the low-power frequency.Secondary power circuit 64 comprises the series tuning tank circuit, and this tank circuit has electric capacity 92 and the coil 94 that is tuned to the low frequency level equally.In form shown in the TET system, by mating high Q value, low-impedance elementary tuning tank circuit 84 and low reactance-resistance ratio, low-impedance secondary tuning tank circuit 90, low elementary feed circuit 56 transmit about 1 watt power at the 10kHz especially resonant frequency below the 5kHz.

In the present invention, elementary feed circuit 56 are worked under the low frequency level so that communicate by letter with secondary power circuit 64 effectively by the implanted device housing.In this was discussed, term " low frequency " or " low frequency level " expression were lower than the frequency of 100 kilo hertzs (kHz).As mentioned above,

power coil

88,94 also at the low frequency low-resonance so that secondary power coil 94 can be enclosed in the implanted device housing of sealing.

For through-put power under the low frequency level and remote measurement

magnetic field

62,42,54, traffic filter 96 filters the electric signal that receives on the secondary transceiver 44, particularly is the electric signal from tank circuit 78. and wave filter 96 can be the filter design that is selected to any kind of the frequency of prevention except the remote measurement resonant frequency from the more low-yield remote measurement of higher-energy power field 64 uncouplings magnetic field 42. wave filters 96.

Fig. 3 has shown a canonical form that is applicable to wave filter 96 of the present invention.In the present invention, the command signal from elementary or secondary telemetry coil 82 is applied to a series of single pole and low pass and the high-pass filtering section of isolating telesignalisation and TET power signal.For first order pole embodiment shown in Figure 3, AC

magnetic field

62,42,54 alternately is being transmitted in the time period, thereby eliminates the high Q value of power field 62 from telesignalisation 42,54.In another embodiment, wave filter 74 comprises one or more two-pole filters, for example Chebyshev (Chebyshev) wave filter.This 2 utmost point wave filter provides the more effective filtering of high Q value power signal, and AC

magnetic field

62,42,54 can be transmitted simultaneously.From the more low-yield telesignalisation of higher-energy power signal filtering, the resonant frequency of two signals differs an order of magnitude at least for effectively.

Fig. 4 A and 4B have shown respectively the

magnetic field

62 and 42/54 that is radiated subcutaneous secondary TET coil 94 and telemetry coil 82 from prime power coil 88 and primary. transceiver coil 76.In the form shown in Fig. 4 A,

magnetic field

62 and 42/54 all has two toroidals, it penetrates secondary TET power and

telemetry coil

94,82 that physical boundary 30 arrives separately only more shallowly, reduces the NE BY ENERGY TRANSFER between the coil thus and correspondingly needs implanted device 22 as for more shallow position.Fig. 4 B has shown an alternative embodiment of the invention, its name of quoting in front is called in the patented claim of " have high aspect ratio ferrite core through skin NE BY ENERGY TRANSFER primary coil " to be described in more detail, wherein prime power and

transponder coil

56,66 are placed around magnetic conductance ferrite core 98.Shown in Fig. 4 B, the adding of ferrite core 98 has caused

magnetic flux

62,42/54 to draw to magnetic core 98 from primary coil 88,76.Therefore

magnetic field

62,42/54 radially be collapsed in the magnetic core 98 and from circle and become ellipse.

Magnetic field

62,42/54 ground elliptical shapes have increased the coupling efficiency between primary and

secondary telemetry coil

76,82 and the primary and secondary power coil 88,94.And the coupling efficiency of the increase between the ferrite core 98 is in bigger physical distance or in the remote measurement that has improved under the low power level between the transceiver 32,44.

In a typical embodiment of the present invention, each primary and

secondary transponder coil

76,82 is all formed by No. 36 (gauge) winding wires of 220 circles.Each

coil

76,82 all has the electric capacity placement in parallel of the resonant frequency of about 25kHz with causing tank circuit.Prime power coil 88 is formed by the twisted wire of 102 circles, this twisted wire by 100 independently No. 30 (gauge) insulated wire astragals form.Described winding wire is in parallel with the electric capacity of 9.2 microfarads, and this has formed and has had the especially in parallel tuning tank circuit of the following resonant frequency of 5kHz of high Q value and 10kHz.Prime power coil 88 and elementary telemetry coil 76 all are placed on around the ferrite core 98 with 3 inchages and 0.75 inch diameter.Use these parameters and resonant frequency, the about 1 watt of power of prime power coil 88 transmission, and elementary telemetry coil 76 transmission milliwatt level power.Power and 88,76 alternate transmission a period of times of telemetry coil, and telemetry system 16 is transmitted data under the baud rate of 1kHz.In this EXPERIMENTAL EXAMPLE, separate 3 inches distance between the primary and secondary coil.

When being the medical treatment device design low frequency telemetry system of dark implantation, wish to make the Q value of two magnetic coupling telemetry coils in the tuning tank circuit in parallel in the scope of 10-20.If the Q value of these two tank circuits is lower than this scope, will be difficult to realize any effective deep penetration remote range so.If the Q value is higher than this scope, the tuning tank circuit of not tuning individually every pair of parallel connection just is difficult to make in large quantities this system so.

Also can make elementary (or outside) remote measurement tank circuit have very large Q value (greater than 100) and in implanted device, have lower Q value (about 10) simultaneously.Compare the advantage of doing like this and be with have high Q value circuit in implanted device, higher Q value needs bigger and heavier coil and bigger inductance usually.This is provided with in the effective frequency range that the natural frequency that will still allow high Q value circuit is included in the low reactance-resistance ratio circuit and does not need independent tuning or match circuit.

Coil in dark implantation telemetry system can make their coil turn maximum with coupling and the AC magnetic field that produces better as the remote measurement media better. need under the resonance of the tuning tank circuit of parallel connection, not produce tangible high impedance when doing like this, open cross sectional in the coil periphery need be maximized so that improve magnetic coupling between the tank circuit. and the coil of use has No. 36 winding wires of 220 circles, when in parallel with the electric capacity of 5600pF, produce the resonant frequency of 25kHz, and the Q value of calculating is 19, the impedance of calculating under resonance is approximately 20 kilo-ohms. because parasitic loss and other non-linear effects, actual Q value is always than the low about 10%-30%. of calculated value

Although the present invention is for example understood in the description by several embodiment, although and described in detail cited embodiment, the application's purpose is not to be or to be limited to this details by any way with the scope restriction of accessory claim.Other advantage and improvement are conspicuous for those skilled in the art.

For example, although described telemetry system 16 has the special advantage that is used for implantable medical device system 10, a plurality of schemes according to the invention have for other science that comprises xenobiotic reason border and the application of engineering proposal.For example, can be applicable to that hope can monitor and/or controlling packet is contained in the driver in the container and do not damage in the treating apparatus of integrality of the container that has the lead that passes wherein or pipeline.

And telemetry system 16 can be used to lack the situation of TET power system 14.As another selection, telemetry system 16 can provide the one-way communication passage but not duplex channel.

Claims

1. telechirics comprises:

Elementary controller is in order to import and to receive the order data signal from user or automatic programming device;

Elementary telemetry transmitter, its by described elementary controller excitation and comprise with the electric capacity electric connection to form the primary coil of tank circuits, this tank circuits has 100kHz or following peak resonance;

Secondary controller; And

Secondary telemetry receiver, it transmits the electromagnetic energy that is transferred to the reception of described secondary controller from described elementary telemetry transmitter, and comprise and the secondary coil of electric capacity electric connection that this tank circuits has 100kHz or following peak resonance with the formation tank circuits

Wherein the electric command signal that will produce in described secondary telemetry receiver is applied to described secondary controller.

2. according to the telechirics of claim 1, the peak resonance of the tank circuits of wherein said elementary telemetry transmitter and secondary telemetry receiver is between 25-100kHz.

3. according to the telechirics of claim 1, further comprise the medical implant apparatus shell of described secondary controller of sealing and described secondary telemetry receiver.

4. according to the telechirics of claim 1, wherein said coil further comprises the ferrite core of vertical arrangement.

5. according to the telechirics of claim 1, wherein said primary coil comprises multiturn insulation twisted wire.

6. according to the telechirics of claim 1, wherein said secondary coil comprises the multiturn twisted wire.

7. according to the telechirics of claim 1, wherein said elementary controller and elementary telemetry transmitter are positioned at the outside of a physical boundary, and separate on described secondary controller and the secondary telemetry receiver space.

8. according to the telechirics of claim 6, wherein said elementary telemetry transmitter comprises primary. transceiver, and secondary telemetry receiver comprises the secondary transceiver that is used for bidirectioanl-telemetry and control.

9. according to the telechirics of claim 1, further comprise the bandpass filter between described secondary telemetry receiver and the secondary controller.